1. Field of the Invention
The present invention relates to an image processing apparatus and, more particularly, to an image processing apparatus arranged to detect the outline of input image data and then to effect color conversion of the detected outline.
2. Description of the Related Art
In recent years, widespread use has been found for digital color copying machines which are arranged first to read a color original by utilizing a digital color separation process, second to apply a desired process to the thus-read digital image signal, and third to produce a color copy on the basis of the digital color image signal obtained. In order to faithfully reproduce the color and sharpness of the original, this kind of apparatus is designed first to read an image signal by means of a CCD, second to convert the image signal into a digital signal by means of an A/D converter, and third to apply various processes, such as color masking, under color removal, tone compensation and the like. Particularly recently, digital color copying machines have been proposed which are provided with a simple form of a color-image processing function such as cutting, moving, synthesizing or the like. In such a situation in which the degree of fineness of recorded images is improved and the number of functions incorporated into a copying machine increases, it has been strongly desired to realize, in addition to the above-described color-image processing function, the color conversion function of replacing image data representing the color of a particular region on an original with data representing a different color.
However, in a case where such color conversion is conducted with a proposed method or apparatus, if the color of a character body on an original is color-converted, the outline of the character body is also converted into the same color. Accordingly, if the outline and the character body of a particular character are to be emphasized independently of each other, it has been necessary to draw the outline portion by hand with a color pen or the like. This problem applies to not only emphasis on characters but emphasis on graphics.